rails-migrations

I had an add_column migration that would run fine. However, after running it and firing up a console, I would find the first_name and last_name columns completely empty. I tried using save! instead and it had the same effect--no errors reported. Here's the original: class UserAddFirstNameAndLastName < ActiveRecord::Migration def change # add column first name, last name string add_column :users, :first_name, :string add_column :users, :last_name, :string User.all.each do |u| u.first_name = 'first name' u.last_name = 'last name' u.save end end end I also thought this might be some class loading

Is it permissible to delete (or archive) old migration files in a Rails app if the schema is stable? My migrations are numerous and I suspect there may be some problem in there somewhere, because I occasionally have problems migrating the database on Heroku. Zack Xu You don't need to keep around your old migration files in a Rails app, because your database schema should be captured either in schema.rb or an equivalent SQL file that can be used to regenerate your schema. Migrations are not the authoritative source for your database schema. That role falls to either db/schema.rb or an SQL file

With performance improvements in mind, I was wondering if and which indexes are helpful on a join table (specifically used in a Rails 3 has_and_belongs_to_many context). Model and Table Setup My models are Foo and Bar and per rails convention, I have a join table called bars_foos . There is no primary key or timestamps making the old fields in this table bar_id:integer and foo_id:integer . I'm interested in knowing which of the following indexes is best and is without duplication: A compound index: add_index :bars_foos, [:bar_id, :foo_id] Two indexes A. add_index :bars_foos, :bar_id B. add

Is it possible to completely remove the database and all migration records etc from an existing application so I can redesign the database from scratch? Paulo Fidalgo By issuing rake -T you have the following database tasks: rake db:create # Create the database from DATABASE_URL or config/database.yml for the current Rails.env (use db:create:all to create all dbs in the config) rake db:drop # Drops the database using DATABASE_URL or the current Rails.env (use db:drop:all to drop all databases) rake db:fixtures:load # Load fixtures into the current environment's database rake db:migrate #

I'm in the process of adding Devise to an existing Rails app, with a Users table already defined. The devise generator pushed out the following migration: class AddDeviseToUsers < ActiveRecord::Migration def self.up change_table(:users) do |t| ## Database authenticatable t.string :email, :null => false, :default => "" t.string :encrypted_password, :null => false, :default => "" ## Recoverable t.string :reset_password_token t.datetime :reset_password_sent_at ## Rememberable t.datetime :remember_created_at ## Trackable t.integer :sign_in_count, :default => 0 blah blah blah.... end add_index

Can someone give me a short introduction to doing DB migrations in Rails using Mongoid? I'm particularly interested in lazy per document migrations. By this, I mean that whenever you read a document from the database, you migrate it to its latest version and save it again. Has anyone done this sort of thing before? I've come across mongoid_rails_migrations , but it doesn't provide any sort of documentation, and although it looks like it does this, I'm not really sure how to use it. I should point out I'm only conceptually familiar with ActiveRecord migrations. If you want to do the entire

I'm getting an error: SQLite3::SQLException: no such column: ideas.list_id: SELECT "ideas".* FROM "ideas" WHERE "ideas"."list_id" = 2 But I added t.integer :list_id to my db migration file: class CreateIdeas < ActiveRecord::Migration def change create_table :ideas do |t| t.string :name t.text :description t.string :picture t.timestamps end add_foreign_key :ideas, :lists end end which gave me this: class CreateIdeas < ActiveRecord::Migration def change create_table :ideas do |t| t.string :name t.text :description t.string :picture t.integer :list_id t.timestamps end add_foreign_key :ideas,

It is easily possible to remove a column using rails migration. class SomeClass < ActiveRecord::Migration def self.up remove_column :table_name, :column_name end end I want to know if there is any way to remove a column from table using console. You can run the codes in up method directly in rails console : >> ActiveRecord::Migration.remove_column :table_name, :column_name If you already have a migration file such as " db/migrate/20130418125100_remove_foo.rb ", you can do this: >> require "db/migrate/20130418125100_remove_foo.rb" >> RemoveFoo.up If you just want to do rake db:migrate , try

I have a rake task that won't work unless a table exists. I'm working with more than 20 engineers on a website so I want to make sure they have migrated the table before they can do a rake task which will populate that respective table. Does AR have a method such as Table.exists ? How can I make sure they have migrated the table successfully? In Rails 5 the API became explicit regarding tables/views , collectively data sources . # Tables and views ActiveRecord::Base.connection.data_sources ActiveRecord::Base.connection.data_source_exists? 'kittens' # Tables ActiveRecord::Base.connection.tables

I want do run migration on my app that I have on heroku but I get this error: Running `rake db:migrate` attached to terminal... up, run.1 DEPRECATION WARNING: You have Rails 2.3-style plugins in vendor/plugins! Support for these plugins will be removed in Rails 4.0. Move them out and bundle them in your Gemfile, or fold them in to your app as lib/myplugin/* and config/initializers/myplugin.rb. See the release notes for more on this: http://weblog.rubyonrails.org/2012/1/4/rails-3-2-0-rc2-has-been-released. (called from <top (required)> at /app/Rakefile:7) DEPRECATION WARNING: You have Rails 2.3